Hello all!
Do any of you know what this bracket is do? Maybe someone has a photo of this part in the vehicle? Can't see it on the parts diagrams. I just assemble the door after a long break and I do not know what this part is do.

Well that's new.  Looks more like a custom tool for aiding installation of something...

That’s actually a bracket that holds the window channel in place. The screw in bit will go into the door beam using a sliding captive nut. 
You’d need to look on the parts diagram to see where it goes exactly, but that’s what it’s for. It allows adjustment to get the window frames nicely aligned.